The circular mirror with a centered hole to look through that doctors and dentists, herein practitioners, wore to reflect ambient room light toward the patient was low cost but dependent on available light thus ineffective. Those were compact, lightweight and relatively low tech. Studies have been made of the best electrical light and how to deliver that to the surgical site so the practitioners can easily see the work to be done. So far the common practice is an overhead light that can be angled to aim it toward the area of concern, interest and surgery. Those overhead lights have to be adjusted and readjusted. The practitioner touches them so they have small protective antiseptic booties over their handles and require the aversion of the eyes from the patient to the light during the readjustments. also they are substantially spaced from the surgical site and thus need to be high wattage and focused to put illumination just where required so the practitioner typically has to look back and forth between the light and the surgical site. a light that always shines on the surgical site where the practitioner is working and looking would reduce the interruptions in concentration and focus on the medical procedure being performed is needed.
Studies show psychological effects of good illumination on the visual acuity and success of endeavors. Melatonin hormone controls the circadian rhythm and the performance of animals and humans. In periods of darkness, melatonin reduces cardiovascular activity and induces fatigue. Morning light inhibits melatonin secretion in the pineal gland, which increases cardiovascular activity. Melatonin inhibition peaks at 450 nm in the continuous visual spectrum, i.e. in the blue spectral range. Light containing a large proportion of blue wavelengths therefore inhibits the secretion of melatonin in the pineal gland. If these blue wavelengths are absent (reddish light), melatonin secretion is uninhibited, which produces fatigue, recent research, lead by Professor Dietrich Gall, head of the Lighting Technology Department, at Ilmenau University of Technology, Germany, with the cooperation of the lighting firm Berchtold GmbH & Co. KG, of Tuttlingen, in the USA Berchtold Corporation□1950 Hanahan Road□Charleston, S.C. 29406□ analyzed lighting as a form of radiation and the potential psychological effects of its dose level on doctors, dentists and surgeons.
Consequently, light having the proper wavelengths and intensity and aimed at the area of doctor effort and scrutiny is of paramount importance for a successful and good result and often may be life saving. Past efforts to illuminate a surgical site or area of concern and investigation by the practitioner have been less than compact, portable, safe and reliable in performance.
In 2002, Professor Gall succeeded in describing the circadian effect of light in mathematical terms, defining the circadian effect coefficient (acv coefficient) as the ratio between the visual utilization effect (taking the photoreceptors' effect curve into account) and the circadian utilization effect (taking the effect curve of the circadian retinal receptors into account). So it became possible to measure the circadian effect of light, and provide a simple means to describe the physiological effect of light. Volker Dockhorn, engineer and Product Manager, OR-Lights, Berchtold, explained that the goal was to determine whether surgical lights of different color temperatures produced different physiological effects on a surgeon, and use that knowledge to deliberately reduce fatigue and improve their wakefulness when working at night. Since 1929, CHROMOPHARE® lights have led the market in surgical equipment technology. Quality surgical lighting illumination and consultant's knowledge of efficient and versatile operating room design set BERCHTOLD apart in the market. CHROMOPHARE® X 65:Tn: 4300 K—acv undimmed: 0.60—acv dimmed: 0.60—remark: opto-mechanical dimming. CHROMOPHARE® D 650 plus Tn: 4300 K—acv undimmed: 0.59—acv dimmed: 0.51—remark: electronic dimming. Comparative light Tn: 3400 K—acv undimmed: 0.45—acv dimmed: 0. Results of measurements of the circadian effect coefficient for three surgical lights all lights were first measured at an luminance of 100,000 lux and subsequently with luminance dimmed to 50% Table 1 presents results of measurements of the circadian effect coefficient (acv coefficient) for three surgical lights, one gas discharge light (BERCHTOLD® CHROMOPHARE® X 65), one halogen light with a high color temperature of 4,300K (BERCHTOLD® CHROMOPHARE® D 650plus) and one halogen light of comparable size, from another firm, with a lower color temperature of 3,400K and a large red component. All lights were first measured at a luminance of 100,000 lux and subsequently with luminance dimmed to 50%.
The results described would suggest that the gas discharge light CHROMOPHARE® X 65 and the halogen light CHROMOPHARE® D 650plus, with its high color temperature (4,300K), cause less fatigue, whereas it would be expected that surgery performed under a halogen light with a lower color temperature (3,400K) would cause greater fatigue, especially at night.
To verify this outcome, the study examined the performance and concentration of 55 participants. In one group, 30 people carried out tests in winter; in the other, 25 performed them in summer, to determine seasonal effects. Experiments were limited to a study of the difference in effect between the two-halogen lights, which initially irradiate a similar spectrum. The color temperature difference between the two lights arises through selective filtering of the wavelength spectrum by light manufacturers.
The irradiated surface was flat, and its reflectivity was therefore higher (76%) than is usually the case with human tissue. For this reason the luminance of both lights was adjusted to 40,000 lux, by altering the size of the light field. The light field diameter was the same for both. The acv value for the halogen light with high color temperature was 0.59, while for the one with lower color the temperature was 0.45, said Volker Dockhorn.
The participants did not know which lights were being used. To induce a general state of fatigue, such as results through mental work, the participants were asked to solve arithmetical problems under time pressure. Then the d2 test was performed, to determine a subject's performance capability and power of concentration. The sequence in which the lights were used was altered from one test to the next. 50% of participants began the tests under the light with high color temperature (BERCHTOLD®), then, following an adaptation interval, performed them under the light with lower color temperature. The remaining 50% began tests under the reference light. On average, participants working under the BERCHTOLD® light answered 502 questions; those working under the reference light answered only 485 questions, equivalent to a 3.5% improvement in performance by those working under the BERCHTOLD® light. Statistical error probability was 0.069 in this case, i.e. only slightly short of the significance threshold (0.05), and it is therefore justified to point to a trend.
If, as a means to determine power of concentration the number of questions answered correctly is considered, the difference was even more pronounced. On average, under the BERCHTOLD® light 205 questions were answered correctly, whereas under the reference light 195 questions were correct an average, 5.1% lower than in the case of the reference light. The result has an error probability of 0.041, i.e. within the significance threshold of 0.05. Therefore, in winter, a significant increase in power of concentration and a decrease in error frequency were found in work performed under the BERCHTOLD® light with a high color temperature of 4,300K.
The scientists presume that the results would diverge even more if the tests were carried out at night, when melatonin blood levels are higher. However, as it was, even tests carried out during the afternoon or evening showed a clear trend and, in some part, also significant results that appear to confirm the results of the physical measurements.
Thus the study has proved that a high color temperature of 4,300 as irradiated by a CHROMOPHARE® D 650 plus light can enhance a surgeon's performance capability during the winter (trend). Work performed under a surgical light of low color temperature (3,400 K) is subject to a significantly greater error frequency. During night surgery, when a surgeon's melatonin blood level is high, this effect is thought particularly pronounced.
Headlight assembly United States Patent Application number 20070236955 and discloses portable fan cooled light with optics for surgery. That teaching is missing is the importance of maintaining color temperature ideal for a surgeon to see different anatomical structures and reduce fatigue. In the background thereof it includes, one problem associated with known dental loupe lights is that the housing of the light source is typically secured to a bench adjacent the dental professional so as to be fixed, i.e., stationary and immobile. The mounting is needed due to the size and design of that headlight and cooling fan. By being fixed or having poor design, the movement of the dental professional is hampered and restricted during dental procedures. additionally, the length and fixed headlight end or proximal plane of the fiber optic cable disclosed would no doubt impede the ability of the dental professional to move or manipulate various instruments during the dental procedure, which can result in the fiber optic cable being damaged or otherwise compromised.
Any light source capable of proper illumination will consume a significant amount of energy and create heat. The light source used in conjunction with the fiber optic cable and any focusing optics can provide a single defined beam that does not interfere with its use. The light source can be configured to emit light characterized as substantially 5500 Degrees Kelvin or “noon day” sunlight. Accordingly, the light emitter can include a plurality of LEDs that cooperate to emit the light. Alternatively, the light emitter can include a halogen, HID, or other lamp that can be filtered so as to emit the light. HID lights have no filament to burn up so they last ten times longer that common halogen lamps. The lamp is filled with xenon gas that is excited by high voltage 20,000 volts direct current creating light intensity equivalent to daylight 6000 Degrees Kelvin in color temperature. another benefit is that only 2.9 amperes are required using about 35 watts. a ballast and igniter are required to energize 12 volts to the high voltage needed for the excitation of the xenon. Optimization of low power lamp achieving an average used illumination output with performance equivalent to a 300-watt xenon lamp by reducing overall radio frequency infrared output reducing shielding required when plugged into a wall unit while also reducing the heat and safety concerns. Light output is comparable to a stand 300-watt xenon unit that is plugged into the wall using the wall circuitry for its shielding and cooling. The disclosed battery powered unit has the ability to be flexible enough to be un-tethered allowing freedom of movement with its compact portable design configuration and minimized shielding needs releases it from being plugged into the wall. The high wattage system used in a interior or minimally invasive hip procedures with a plugged in unit is often placed under the surgical table covered and separated with a sterile draped to maintain a sterile field increases the chance of fire as compared to the presently disclosed belt worn battery low wattage that does not have that risk and also enables the user to move about freely without assistance. The disclosed cordless headlight assembly may be carried within a personal environmental surgical suit primarily used by orthopedic surgeons while performing hip and joint surgeries allowing them to move around the surgical table when they need to articulate body parts. More progressive surgeons move the plug-in versions under the table requiring a nurse to reach underneath the table plug and unplug the headlight fiber optic cable. also by having the cords and cables at their feet movement of the two surgeons working side-by-side causes them to step on the cables cause damage. The disclosed portable unit in surgery permits ease of movement and no incidence of damage to the cables as they are carried by the surgeon(s) out of harm's way. The plug in fiber optic cables can fall into the sterile field during surgery compromising the sterility of the procedure. Using the disclosed fiber optic headlight eliminates that even when using the environmental helmet or the stand headlight version.
Furthermore, the cooling of lighting devices that typically generates a substantial amount of heat has resulted in its placement being fixed and/or remote from the loupe columniation lens. In part, this is because the heat generated from the light source has caused its housing to become hot, which will injure the practitioner or assistant that comes too close or accidentally touches the hot housing accordingly, that patent application teaches and explains that there is a benefit of a lighting apparatus that includes a headlight that is thermally disconnected from the light source and fan housing. Even though, that patent application recognizes as beneficial for the lighting apparatus to include a cooling apparatus so that the temperature of the light source housing would be held below a potentially dangerous or harmful temperature, that has not been refined to the level of the present disclosure of a compact portable headlight assembly as will be disclosed. Not appreciated or understood in that patent application are the benefits of a surgical site illumination with various components, housed together in proximity and wherein the light is selectively directed into the optic fiber cable. Furthermore, it would be beneficial for the apparatus to be portable and/or usable with the optic fiber cables of various lengths and loupes that are also interchangeable as needed. The light source can be any lamp that emits light. Such a lamp can be a halogen lamp, high intensity discharge (HID) lamp, array of light emitting diodes, LEDs, etc. Operating rooms in many hospitals lack floor space for added new technology including important instrumentation. The disclosed surgical headlight offers a compact solution. Removal of large high wattage headlight would revolutionize the way that surgical headlights are used in the operating room. The disclosed compact portable high light configuration meets the needs of the surgeons and is low wattage but with sufficient illumination of the surgical site.
An example of a light source can be found in U.S. patent application Ser. No. 11/339,288, which is incorporated herein in its entirety by specific reference notes the spectrum or color temperature of the light emitting diodes of the light source can be tuned. This allows for the spectrum or temperature of the light to be adjusted as desired or needed. For example, the spectrum of light emitted by the light source may deviate from the noonday sunlight spectrum about 5200 Degrees Kelvin to about 6600 Degrees Kelvin over time, and tuning the spectrum can re-achieve the desired spectrum. also, the spectrum can be tuned and adjusted during manufacturing. alternatively, there may be situations where light that does not approximate the noonday sunlight spectrum is desired or needed, where tuning may alter the spectrum away from noonday sunlight. In addition, the color-rendering index produced with the present invention is significantly improved compared to conventional devices and the resulting light spectrum can more closely simulate noonday sunlight. as such, the spectrum can be characterized as being from about 5200 Degrees Kelvin to about 6600 Degrees Kelvin, more preferably from about 5400 Degrees Kelvin to about 6000 Degrees Kelvin, and most preferably about 5500 Degrees Kelvin. Notably there is no teaching of portable cooled high intensity discharge lamps in this application or the importance of lighting safely anatomical structures with safety and freedom of movement available to a practitioner.
Portable headlight assembly of United States Patent Application 20080085111 adds a camera to the concept and mentions a high intensity discharge lamp but it still does not address portability and safety.